IOWA CITY — Jonathan Wieseler, 34, the bail bondsman found dead in his office Sunday morning, was shot to death, according to police.

The Iowa City Police Department on Wednesday released the preliminary results of Wieseler’s autopsy. The cause of death was determined to be a gunshot wound and the manner of death was determined to be homicide, authorities said.

Police do not have anyone in custody, but believe Wieseler’s death is an “isolated incident,” they said in a news release.

Sgt. Scott Gaarde said police cannot comment on several aspects of the investigation, including whether a suspect has been identified or if a weapon has been recovered. Police have apparently narrowed down the hours during which they believe Wieseler died. Investigators are asking for any information on people seen in the area of Lederman Bail Bonds, 518 S. Capital St., between 10 p.m. Saturday and 3 a.m. Sunday.

Iowa City police responded to Lederman Bail Bonds, where Wieseler worked, at 11:11 a.m. Sunday after Wieseler’s body was found inside.

Anyone with information about potential leads in the case is asked to call investigator Mike Smithey at (319) 356-5452.

Also, Iowa City Area CrimeStoppers is offering a reward of up to $1,000 for information leading to the arrest of a suspect in the case. Those with information can contact CrimeStoppers at (319) 358-8477.

According to his obituary, Wieseler earned his bachelor’s degree in political science in 2005 and his law degree in 2009 from the University of Iowa. He also earned a bachelor’s degree in biology from the University of Minnesota.

A native of Sioux City, Wieseler served as a volunteer with the Alzheimer’s Association and was a member of Iowa City Learning Foundation, according to his obituary.

He was to be married on June 24, his obituary states.

Wieseler is survived by his fiancée Harmony Hauser, mother Linda Wieseler and his sister, Jennifer Stokes, along with several other family members. He was preceded in death by his father Roman.